(287) Nephthys ( lat. Nephthys ) is one of the typical asteroids of the main belt , which belongs to the light spectral class S. The asteroid was discovered on August 25, 1889 by the German-American astronomer K.G. F. Peters at the Litchfield Observatory , located near the city of Clinton, New York , USA and named after Nephthys , the youngest of the children of Hebe and Nut in Egyptian mythology [1] .
| (287) Nephthys | |
|---|---|
| Asteroid | |
| Opening | |
| Discoverer | C. G. F. Peters |
| Place of discovery | Clinton |
| Discovery date | August 25, 1889 |
| Eponym | Petroleum |
| Category | Main ring |
| Orbital characteristics | |
| Age of March 14, 2012 JD 2456000.5 | |
| Eccentricity ( e ) | 0,02350 |
| Semimajor axis ( a ) | 351.99 million km (2.35291 AU ) |
| Perihelion ( q ) | 343.719 million km (2.29762 AU) |
| Aphelion ( Q ) | 360.262 million km (2.4082 AU) |
| Circulation Period ( P ) | 1318.276 days (3.609 g. ) |
| Average orbital speed | 19,415 km / s |
| Inclination ( i ) | 10,027 Β° |
| Longitude node (Ξ©) | 142.442 Β° |
| Perihelion Argument (Ο) | 117.847 Β° |
| Median Anomaly ( M ) | 357.388 Β° |
| physical characteristics | |
| Diameter | 67.60 km |
| Weight | 3.23β 10 17 kg |
| Density | 2,000 g / cmΒ³ |
| Acceleration of free fall on the surface | 0.0189 m / sΒ² |
| 2nd space speed | 0.0357 km / s |
| Rotation period | 7,605 h |
| Spectral class | S |
| Apparent magnitude | 12.61 m (current) |
| Absolute magnitude | 8.30 m |
| Albedo | 0.1851 |
| Average surface temperature | 177 K (β96 Β° C ) |
| Current distance from the sun | 2,301 a. e. |
| Current distance from earth | 1.85 a. e. |
Content
Orbital characteristics
This asteroid is located in the inner part of the main belt at a distance of 2.35 a. e. from the sun. Since it moves in an almost circular orbit with a low eccentricity close to 0.023, its distance from the Sun varies rather weakly, from about 343.719 million km perihelion to 360.262 million km aphelion .
- Orbit of the asteroid Nephthys and its position in the solar system
An asteroid makes one revolution around the Sun in about 1318.3 days, which is just over 3.6 years.
Physical Characteristics
The diameter of the asteroid is relatively small, only 67.60 km. Its surface is very light, with an albedo of 0.1851, which indicates its belonging to class S silicate asteroids. Due to its small size and relatively small reflectivity, the absolute magnitude of the asteroid is only 8.30 m , and its apparent magnitude is even smaller.
The rotation period around its axis is a little more than 7 hours and 36 minutes.
See also
- The list of asteroids ( 201-300 )
- Classifications of Minor Planets
Notes
- β Schmadel, Lutz D. Dictionary of Minor Planet Names . - Fifth Revised and Enlarged Edition. - B. , Heidelberg, N. Y .: Springer, 2003 .-- P. 40. - ISBN 3-540-00238-3 .